A device for assisting a rescuer in delivering therapy to an adult or pediatric patient, the device including a user interface comprising a display and/or audio speakers, the user interface being configured to deliver prompts to a rescuer to assist the rescuer in delivering therapy to a patient； a processor configured to provide prompts to the user interface and to perform an ECG analysis algorithm on ECG information detected from the patient； at least one detection element configured to determine without rescuer input via the user interface that a pediatric patient is being treated； wherein, if a pediatric patient is detected, the processor modifies the ECG analysis algorithm or the prompts provided to the user interface to use an ECG analysis algorithm or prompts adapted for a pediatric patient rather than for an adult patient.
